Semiconductor memories, such as dynamic random access memories (DRAMs), are used in a wide variety of applications, such as personal computers, servers, graphic cards, digital televisions, and cell phones, for example. While DRAMs typically employ one of several standard architectures, the particular implementation of the architecture of a given DRAM is typically modified to meet the specific needs of the application in which the DRAM is being employed, such as to provide the highest performance (access speed) or to provide the lowest power consumption, for example.
The access speed of a DRAM is affected by parameters including block size, word line length, and bit line length, for example, with the access time of the entire DRAM being determined by the DRAM memory cell having the longest runtime or access time. As a result, for a given application, a DRAM meeting the requirements of the application data having the highest access speed requirement is selected, even though the majority of the overall application data has access speed requirements which could be met using a less costly DRAM having a slower access speed. As an alternative, a high speed cache memory device is often employed for data requiring high access speed, with a lower speed DRAM being employed for a remainder of the application data. However, employing separate memory devices is also costly.